問題一覧
1
An airplane wing is designed to produce lift resulting from
Positive air pressure below the wing's surface and negative air pressure above the wing's surface along with the downward deflection of air.
2
Which is the ratio of the water vapor actually present in the atmosphere to the amount that would be present if the air saturated at the prevailing temperature and pressure?
Relative humidity
3
A wing with a very high aspect ratio (in comparison with a low aspect ratio wing) will have
A low stall speed
4
The main rotor system on a helicopter is classified in three groups. Which of those listed is NOT one of these groups?
The flexible-beam rotor system.
5
Which of the following is NOT considered a method of heat transfer?
Diffusion
6
The speed of sound in the atmosphere is most affected by variations in which of the following?
Ambient temperature
7
If all or a significant part of a stall strip is missing on an airplane wing, a likely result will be
Asymmetrical lateral control at or near stall angles of attack.
8
The speed of sound in the atmosphere
Changes witha change in temperature.
9
Which will weigh the least?
35 parts of dry air and 65 parts of water vapor
10
The purpose of stall strips on airplane wings is to
Ensure the the wing root areas stall first.
11
Which condition is the actual amount of water vapor in a mixture of air and water?
Absolute humidity
12
Aspect ratio of a wing is defined as the ratio of the
Wingspan to the mean chord
13
Under which conditions will the rate of flow of a liquid through a metering orifice (or jet) be the greatest (all other factors being equal)?
Unmetered pressure, 17 PSI; metered pressure, 5 PSI; atmospheric pressure, 14.7 PSI
14
If both the volume and the absolte temperature of a confined gas are doubled, the pressure will
Not change.
15
"In phsyics, which of the following factors are necessary to determine power? 1. Force exerted 2. Distance moved 3. Time required"
1, 2 and 3
16
Which of the followingg is Newton's First Law of Motion, generally termed the Law of inertia?
Every body persists in its srare of rest, or of motion in a straight line, unless acted upon by some force.
17
An engine is removed from an aircraft by means of a mobile hoist. The engine is raised above its attachment mount, and the entire assembly is then moved forward 12 feet. A constant force of 70 pounds is required to move the loaded hoist. What is the total work input required to move the hoist?
840 foot-pounds
18
Which statement concerningg heat and/or temperature is true?
Temperature is a measure of kinetic energy of the molecules of any substance.
19
The desired effect of using winglets on an aircraft's wingtips to
Increase the lift to drag ratio
20
What is absolute humidity?
The actual amount of water vapor in a mixture of air and water.
21
If a double acting actuating cylinder in a 3,000 psi system has a piston with a surface area of three square inches on the extention side, and a rod with a cross-section area of one square inch attached to the piston on the other side, approximately how much force will the actuator be able to produce when retracting?
6,000 pounds
22
Which of the following statements are correct?
When the collective pitch control lever is raised, the blade angle of all the rotor blades increases uniformly and they create the lift that allows the helicopter to take off vertically.
23
The purpose of aircraft wing dihedral is to
Increase lateral stability
24
If the temperature of a confined liquid is held constant and its pressure is tripled, the volume will
Remain the same
25
The temperature to which humit air must be cooled at constant pressure to become saturated is called
Dewpoint
26
"What force must be applied to roll a 120-pound barrel up an inclined plane 9 feet long to a heigh of 3 feet (disregard friction)? L / I = R / E L = Length of the ramp, measured along the slope. I = Height of the ramp. R = Weight of object to be raised or lowered. E = Force required to raise or lower object."
40 pounds
27
How much work input is required to lower (not drop) a 120-pound weight from the top of a 3-foot table to the floor?
360 foot-pounds
28
The boiling point of a given liquid varies
Directly with pressure
29
If the volume of a confined gas is doubled (without the addition of more gas), the pressure will (assume the temperature remains constant)
Be reduced to one half its original value.
30
If the fluid pressure is 800 PSI in a 1/-inch line supplying an actuating cylinder with a piston area of 10 square inchs, the force exerted on the piston will be
8,000 pounds
31
Which atmospheric conditions will cause the true landing speed of an aircraft to be the greatest?
High temperature with high humidity.